CHR$ can be used to convert a number between 0 and 255 into an ASCII-char and is the inverse of the function ASC.

Numbers outside the range - either negative or greater than 255 - produce the BASIC-error ?ILLEGAL QUANTITY ERROR IN line. When using a wrong type of variable the BASIC-error ?TYPE MISMATCH ERROR IN line appears. When the numerical argument is missing, the BASIC-error ?SYNTAX ERROR IN line is issued.

If you include the converted ASCII-Code of a control character, the control char can be executed by using the BASIC command PRINT.